We plan to continue our studies of the coupling between intermediate metabolism and red cell membrane Na, K-ATPase using 31P nuclear magnetic resonance. Our studies will be directed, in the first instance, at the mechanism responsible for the amplification affect by which a single molecule of the cation transport inhibitor, ouabain, affects the conformation 10 to 1000 copies of glycolytic enzymes coupled to the transport system. As stated in the progress report, we have show an association between the anion transport protein, band 3, and the Na,K-ATPase. We will look for evidence of a similar association with the Ca-ATPase of the red cell membrane. Will the availability of the new 360mHz wide bore superconducting NMR spectrometer, it will be possible to look for other 31P containing substrates in the human red cell which are normally present in much smaller concentrations than 2,3-diphosphoglycerate (2,3-DPG) whose normal 4.3mM concentration is high enough to permit measurments with our older 60 MHz spectrometer. Preliminary evidence with the 360 MHz spectrometer shows that the 2,3-DPG resonance blocks out the other 31P resonances. Consequently, we will investigate techniques for depleting red cells of 2,3-DPG to see if we can bring this substrate to a low enough level for the other resonances to become visible. We plan to extend the anion transport inhibitor studies to include the effect of Cl on the rate of the stilbene induced conformational change in band 3. We will characterize the system in the presence of Cl and other halides and study the effect of agents which modify anion transport such as NAP-taurine, Ca and phloretin. The merocyanine dye study will be continued to see if we can determine the physical chemical explanation for the electrical potential sensitivity of these dyes. We will continue our study of the polarization and lifetime of the merocyanine fluorescence in lipid bilayers. If the results are encouraging we will plan to extend the studies to cell membranes.